Biometric identification systems detect and authenticate the identity of a human subject on the basis of unique physiological features, such as fingerprints. Some techniques for biometric identification use vein patterns in the hands or other parts of the body. Vein identification systems that are known in the art transmit infrared illumination through the user's hand, and capture a resulting image in which the veins within the hand appear as dark or bright lines due to variations in the captured infrared intensity. Hand vein authentication is considered to have a high level of authentication accuracy due to the complexity of the vein patterns in the hand. Because the vein patterns are internal to the body, they are difficult to counterfeit. Furthermore, vein imaging is contactless and therefore alleviates hygienic concerns that are associated with common systems that use fingerprints or handprints.